Bird Flu Alarm



Understanding Avian Influenza

Three prominent subtypes of avian influenza virus


Influenza A H5

Potentially nine different subtypes
Can be highly pathogenic or low pathogenic
H5 infections have been documented among humans, sometimes causing severe illness and death
Influenza A H7

Potentially nine different subtypes
Can be highly pathogenic or low pathogenic
H7 infection in humans is rare, but can occur among persons who have close contact with infected birds; symptoms may include conjunctivitis and/or upper respiratory symptoms
Influenza A H9

Potentially nine different subtypes
Documented only in low pathogenic form
Three H9 infections in humans have been confirmed.

Understanding Avian Influenza